It was shown earlier today in a ProPublica report that Facebook’s advertising system gladly surfaced categories like “How to burn jews” and “Hitler did nothing wrong.” Obviously Facebook itself didn’t invent these itself, but scraped them from profiles that had listed the phrases under such headings as “field of study.”

This led to the offensive phrases being listed alongside ordinary hobbies and interests that advertisers may want to target. It’s an inconvenient blind spot to be exposed just now, while Facebook is under fire for inadvertently selling what appear to be politically motivated ads to a network of fake Russian profiles during election season. One wonders if there’s anyone to whom Facebook won’t sell ad space?

But removing the fields in question from consideration for advertising is the right move, since the prospect of intelligently sorting through millions of real and imagined vocations for the occasional abuse is a daunting one.

The fields will remain inadmissible as ad categories “until we have the right processes in place to help prevent this issue.”